Ap. Mayer et M. Lehner, EFFECT OF RANDOM SURFACE AND INTERFACE ROUGHNESS ON THE PROPAGATION OF SURFACE ACOUSTIC-WAVES, Waves in random media, 4(3), 1994, pp. 321-335
Weak random surface and interface roughness leads to a shift of the fr
equency and to damping of surface acoustic waves. In the framework of
perturbation theory with a statistical description of the random rough
ness, a method is described for the calculation of the frequency shift
and the damping constant in terms of the power spectrum of the roughn
ess. It applies to homogeneous media as well as to layered structures
and takes account of piezo-electricity. Calculations on the basis of t
his method require knowledge of the displacement field of the surface
wave and the elastic Green tensor in the absence of surface and interf
ace roughness. The method is then used to calculate numerically the da
mping coefficient of Rayleigh waves propagating at an oblique angle to
the grooves of a random grating ruled on the surface of a homogeneous
halfspace.